widget: move class private data to gtkwidgetprivate.h

We want access to the private data from the action muxer so we can just
move the structures to the gtkwidgetprivate.h header. Alternatively we
could create accessors, but given that we'll probably need to use this
in other areas, seems reasonable to just put it there.

gtk/gtkwidget.c

@@ -484,22 +484,6 @@ typedef struct {
   GCallback  callback_symbol;
 } CallbackSymbol;
 
-typedef struct {
-  GBytes               *data;
-  GSList               *children;
-  GtkBuilderScope      *scope;
-} GtkWidgetTemplate;
-
-struct _GtkWidgetClassPrivate
-{
-  GtkWidgetTemplate *template;
-  GType accessible_type;
-  AtkRole accessible_role;
-  GQuark css_name;
-  GType layout_manager_type;
-  GPtrArray *actions;
-};
-
 enum {
   DESTROY,
   SHOW,

gtk/gtkwidgetprivate.h

@@ -201,6 +201,23 @@ struct _GtkWidgetPrivate
   GdkCursor *cursor;
 };
 
+typedef struct
+{
+  GBytes *data;
+  GSList *children;
+  GtkBuilderScope *scope;
+} GtkWidgetTemplate;
+
+struct _GtkWidgetClassPrivate
+{
+  GtkWidgetTemplate *template;
+  GType accessible_type;
+  AtkRole accessible_role;
+  GQuark css_name;
+  GType layout_manager_type;
+  GtkWidgetAction *actions;
+};
+
 void          gtk_widget_root               (GtkWidget *widget);
 void          gtk_widget_unroot             (GtkWidget *widget);
 GtkCssNode *  gtk_widget_get_css_node       (GtkWidget *widget);